"If global warming gets really nasty, everything from energy harvesting to food production is going to get severely stressed and our large human population won’t be sustainable. That’s why our exo-civilization models linked rising planetary impacts with population declines. It was all pretty straightforward, requiring no assumptions about alien economics, sociology, or any other science-fiction ideas."

As I explore in my new book, Light of the Stars: Alien Worlds and the Fate of the Earth, continues physicist Adam Frank in today's Atlantic, our dawning realization that we are profoundly shaping Earth’s future provides us with the impetus to stop acting like cosmic teenagers with power but little wisdom. From that perspective the true narrative of climate change isn’t some small, local drama of Democrats vs. Republications or business interests vs. environmentalists. Instead, it’s a cosmic test, one that gives us a chance to join those who successfully crossed this burning frontier—or the chance to be consigned to the scrap heap of civilizations too shortsighted to take care of their own planet.

The universe does many things, continues Adam Frank in today's Atlantic. It makes galaxies, comets, black holes, neutron stars, and a whole mess more. We’ve lately discovered that it makes a great deal of planets, but it’s not clear whether it regularly makes energy-hungry civilizations, nor is it clear whether such civilizations inevitably drive their planets into climate change. There’s lots of hope riding on our talk about building a sustainable civilization on Earth. But how do we know that’s even possible? Does anyone across the cosmos ever make it?

Remarkably, science has now advanced to point where we can take a first step at answering this question. I know this because my colleagues and I have just published a first study mapping out possible histories of alien planets, the civilizations they grow, and the climate change that follows. Our team was made up of astronomers, an earth scientist, and an urban ecologist.

It was only half-jokingly that we thought of our study as a “theoretical archaeology of exo-civilizations.” “Exo-civilizations” are what people really mean when they talk about aliens. Astronomers refer to the new worlds they’ve discovered as “exoplanets.” They’re now gearing up to use the James Webb Space Telescope and other instruments to search for life by looking for signs of “exo-biospheres” on those exoplanets. So if we have exoplanets and exo-biospheres, it’s time to switch out the snicker-inducing word “aliens” for the real focus of our concerns: exo-civilizations.

We’re interested in how exo-civilizations develop on their planets. Given that more than 10 billion trillion planets likely exist in the cosmos, unless nature is perversely biased against civilizations like ours, we’re not the first one to appear. That means each exo-civilization that evolved from its planet’s biosphere had a history: a story of emergence, rising capacities, and then maybe a slow fade or rapid collapse. And just as most species that have ever lived on Earth are now extinct, so too most civilizations that emerged (if they emerged) may have long since ended. So we’re exploring what may have happened to others to gain insights into what might happen to us.

Of course, we have no direct evidence relating to any exo-civilizations or their histories. What we do have, however, are the laws of planets. Our robot emissaries have already visited most of the worlds in the solar system. We’ve set up weather stations on Mars, watched the runaway greenhouse effect on Venus, and seen rain cascade across methane lakes on Titan. From these worlds we learned the generic physics and chemistry that make up what’s called climate. We can use these laws to predict the global response of any planet to something like an asteroid impact or perhaps the emergence of an energy-hungry industrial civilization.

To launch our science of exo-civilizations we started with those laws of planets, building the right equations to capture the intertwined evolution of a planet and its young civilization. But planetary laws of physics and chemistry only tell part of the story. If we want to know the possible fates of other civilizations on other worlds, we had to bring some biology to bear too.